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Learning from Past Extinctions — HHMI BioInteractive Video

This 30 minute video explains how past extinctions are measured, and the signs that a sixth mass extinction could be on the way. In the first lecture of the series "Biodiversity in the Age of Humans," Dr. Anthony Barnosky of UC Berkeley describes the fossil record's evidence of five mass extinctions—when more than 75 percent of species went extinct. Mammals are a key group for comparing past and present extinction rates. Many living species are threatened today, but there is still time to avoid a sixth mass extinction. Visit the BioInteractive series page for related videos, and supporting materials for the classroom: http://www.hhmi.org/biointeractive/bi...